Monolithic Power Systems Inc. MP8904DD-LF-Z

Overview

MP8904DD-LF-Z from Monolithic Power Systems is a 500mA adjustable low-dropout linear regulator with 2.5V–6.5V input range, 0.5V–5V output voltage set via external resistor divider, 300mV dropout at full load, and integrated power-good open-collector output. It serves as a precision bias supply in battery-powered mobile devices requiring stable low-noise voltage rails.

For engineers reviewing the MP8904DD-LF-Z datasheet, MP8904DD-LF-Z pinout, MP8904DD-LF-Z application, or MP8904DD-LF-Z equivalent, key selection criteria include its 0.5V feedback reference accuracy, 6µA shutdown current, thermal/current protection, and compatibility with small ceramic capacitors (≥2.2µF input, ≥4.7µF output).

Technical Context

The MP8904 employs a PNP pass transistor architecture enabling ultra-low quiescent current and high PSRR at low frequencies. Its feedback loop references a 0.5V internal bandgap, allowing precise output adjustment across 0.5V–5V using only two external resistors.

Power-good monitoring operates independently of enable control: PG asserts low when output drops >10% below regulation point, with open-collector output compatible with 0–5.5V pull-up supplies. Thermal shutdown activates at 155°C and current limit triggers between 550mA–730mA.

Key Specifications

Pinout & Package

MP8904DD-LF-Z is housed in an 8-pin QFN package (2mm × 3mm, 0.5mm pitch) with exposed thermal pad soldered to PCB ground plane for enhanced heat dissipation (θJA = 55°C/W).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar adjustable LDO applications.

Compared with XC6219B182MR-G and AP2210K-3.3TRG1, MP8904DD-LF-Z uniquely combines full voltage adjustability (0.5V–5V), integrated power-good signaling, and 500mA capability in a 2×3mm QFN-enabling single-part support for multi-rail portable systems without sacrificing sequencing control or accuracy.

Availability

MP8904DD-LF-Z is available at Aetrix Electronics and suitable for wireless modems, GPS navigators, cell phone camera modules, and portable medical sensors requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MP8904DD-LF-Z includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Monolithic Power Systems (MPS) is a fabless semiconductor company specializing in high-performance analog and mixed-signal ICs for power management, motion control, and interface applications.

The MP8904 belongs to MPS's precision low-quiescent-current LDO product line, designed specifically for battery-powered portable electronics demanding ultra-low standby power, tight output accuracy, and robust fault protection.

FAQ

What is the minimum output voltage achievable with MP8904DD-LF-Z?

The MP8904DD-LF-Z achieves a minimum output voltage of 0.5V, determined by its internal 0.5V feedback reference voltage. This is confirmed in the Electrical Characteristics table (VFB = 0.481–0.510V) and Application Information section, where VOUT = 0.5V × (1 + R1/R2) yields 0.5V when R1 = 0Ω (shorted), though practical implementation uses R2 only with R1 omitted or set to zero-ohm jumper.

Can MP8904DD-LF-Z operate with a 2.5V input while delivering 2.5V output?

No - MP8904DD-LF-Z cannot sustain 2.5V output from a 2.5V input due to its 300mV dropout voltage at 500mA. At full load, it requires at least 2.8V input to maintain 2.5V output. The datasheet specifies dropout as "300mV at 500mA" and defines dropout as the VIN–VOUT differential when VOUT drops 1% below nominal, confirming this hard limitation.

Is the exposed thermal pad on MP8904DD-LF-Z required to be connected to ground?

Yes - the exposed pad on the bottom of the QFN package must be soldered to a PCB ground plane. The datasheet explicitly states "Exposed Pad on Backside Connect to GND" in the Package Reference diagram and notes θJA = 55°C/W is measured with the pad connected to 1"² of 1 oz copper, making grounding essential for thermal performance and reliability.

How does the power-good (PG) pin behave during enable/disable transitions?

The PG pin is independent of EN state: it remains high when VOUT is within 10% of regulation, regardless of EN status. During EN-driven shutdown, PG stays high until VOUT collapses below threshold; during startup, PG asserts high only after VOUT stabilizes within tolerance. This behavior is verified in the Typical Performance Characteristic "Enable Turn On/Off" waveforms on page 5.

What is the maximum allowable input voltage for MP8904DD-LF-Z?

The absolute maximum input voltage is +7V (IN to GND), but the recommended operating maximum is 6.5V. Exceeding 6.5V violates Recommended Operating Conditions and risks exceeding safe power dissipation limits even at light loads, as confirmed in the Absolute Maximum Ratings table and Thermal Resistance note.

Does MP8904DD-LF-Z require an output capacitor, and what type is recommended?

Yes - a minimum 4.7µF ceramic capacitor with low ESR is required at the OUT pin, as stated in the Pin Functions section ("Bypass OUT to GND with a ≥4.7μF capacitor"). The datasheet confirms stability with "low-ESR output capacitor" and shows performance validation using 4.7µF X5R/X7R ceramics in all typical application circuits.

How is output voltage accuracy affected by resistor tolerance in the feedback divider?

Output voltage accuracy depends directly on resistor tolerance: for R1/R2 = 40kΩ/10kΩ (2.5V example), ±1% resistors contribute ±2% total error,叠加 with ±2% VFB tolerance yielding worst-case ±4% VOUT error. This is derived from the formula VOUT = VFB × (1 + R1/R2) and confirmed in Table 1's "R1 (Ω)" column specifying "±1%" standard values.